The present invention is directed generally to a contact lens disinfector unit, and more particularly to a disinfector unit including means providing an indication as to attainment of the sterilizing temperature, as well as the number of sterilizing cycles that have been employed since the last incident of cleaning of the lenses.
Contact lenses, both of the hard and soft type, often must be sterilized before they are suitable for use. To this end, each pair of contact lenses is inserted into a separate container or lens case which may also have receptacles therein for holding the right and left lenses spaced apart so they do not become confused. These containers are also commonly referred to as contact lens holders. A quantity of fluid is then administered to the container and then the container is placed into a disinfector unit having a heating block for heating the fluid to a sterilization temperature. The lens case is in direct contact with the heating block and the fluid within the container is in direct contact with the lenses and effects sterilization thereof. After the sterilization temperature has been reached and maintained for a sufficient period of time to effect sterilization of the lenses, the lens case and the contact lenses contained therein are permitted to cool to facilitate removal from the disinfector unit.
While both hard and soft contact lenses should be sterilized periodically, sterilization is more critical with respect to soft contact lenses, and daily sterilization is recommended. The reason for this is that soft contact lenses are hydrophilic, that is somewhat porous and therefor capable of absorption of liquid, which maintains the lenses in a soft condition. The porous nature of the lens material also provides a medium for bacterial growth, and as such soft lenses must be sterilized periodically to prevent infection. As an additional matter, the porous lens material will also absorb proteinaceous material which tends to solidify after repeated sterilizing operations, and as such can affect the lenses' corrective and viewing properties. Lens manufacturers therefore suggested and strongly recommended that the user employ a cleaning solution containing certain enzymes which attack and remove the proteinaceous material, after a prescribed number of sterilizing or disinfecting cycles, as for example once each week.
Heretofore, prior contact lens disinfector units, while generally successful, have not provided the user with heating cycle indicating means of the type contemplated by the present invention. More specifically, the invention illustrated and to be discussed provides an indication that the disinfector unit has reached the sterilization temperature, and also when the unit has cooled. Further, said indicator also indicates the number of sterilizing cycles completed since the last cleaning procedure for the proteinaceous material.
As mentioned above, soft contact lenses should be cleaned every predetermined number of days, such as once a week, for example. Prior disinfector units, however, have not provided a means by which the user may easily determine the number of days which have passed since the contact lenses were last cleaned. This is particularly important inasmuch as a build-up of proteinaceous material on the contact lenses could effect the corrective function of the lenses. Therefore, there further exists a need for a contact lens disinfector unit which includes an indicator to assist the user in determining the number of sterilization cycles which have been employed since the user last cleaned the contact lenses with respect to said proteinaceous material.
It is therefore a general object of the present invention to provide a new and improved contact lens disinfector unit with cycle indicating means to assist the user thereof.
It is a further object of the invention to provide a contact lens disinfector unit which not only indicates that the sterilization temperature has been reached, but additionally includes an indication that the lens case containing the contact lenses and the disinfector unit have sufficiently cooled to facilitate removal of the case from the unit.
It is a further more specific object of the present invention to provide a contact lens disinfector unit which provides the user with the above indications as well as an indication of the number of sterilization cycles which have been employed since the contact lenses were last cleaned, and a further indication when it is again time to clean the contact lenses.
The invention therefore provides a contact lens disinfector unit for sterilizing contact lenses, wherein said lenses are of the type which preferably should be sterilized once each day and periodically cleaned after a predetermined number of days. The disinfector unit comprises a housing including a heating arrangement and circuit means adapted to heat the contact lenses to a sterilization temperature and for terminating the application of heat thereafter to allow the contact lenses to cool for completing a sterilization cycle. The contact lens disinfector unit further includes a sterilization cycle indicating means responsive to temperature changes for providing a first indication responsive to the heating arrangement reaching the sterilization temperature and a second indication responsive to the heating arrangement returning to a reduced temperature or cooled state, and also an indication of the number of sterilizing cycles effected since the last incident of cleaning of the lenses.